Raising ph levels

[julie]

Hi there!


I need to raise the ph in my tanks and was told that Calcium hydroxide (CaOH) would be the best thing to use. However l can't find any - only Calcium Carbonate (CaCO3). Would it be okay to use this?

Also l was advised to use a Potassuim supplement in the system. Does anyone know if Sulphate of Potash which is Potassium Sulphate 41.5% and Sulphur 18.4% would be a good thing to use?
I'd really appreciate some advice!


Many thanks,

Julie

[Murray]

Hi Julie,

The easiest two products to obtain are,

Hydrated Lime for the calcium. Great to raise the pH and works as a buffer. It is not strictly ideal but is ok and works well.
Low cost. About 12.00 for a big bag that will last for years.

Another product easily available is "Eco Rose" which is made from potassium bicarbonate. Once again , not strictly ideal, but will do the job well. Make sure you do not use them together....usually about 2 weeks apart and used alternately.
"Eco Rose" is a useful foliant spray to control Powdery Mildew on cucumbers and the like, so if used this way may well provide the potassium the plants need anyway without the need to use it as a pH adjuster.

[julie]

Thanks for that Murray!!!

[julie]

Okay Murray,


I've found both of those products, but having said that l have absolutely no idea as to how to use them to raise the ph. My tank holds about 800 litres and the ph is 6 at the moment. Do you have any idea at all as to how much of each product (obviously used on an alternate basis and not together )to use daily to bring the ph up to about 7?

How do you apply the stuff?


Thanks for the help!


Julie

[Murray]

Hi Julie,
pH changes must be carried out slowly and in very small increments. If possible do not add the buffer directly to the fish tank. The fish may swim through a patch of buffer and get gill damage because of the extreme difference in pH in a small part of your tank.

Mix up a couple of table spoons on a 4 or 5 ltr bucket of water from the fish tank and pour it into your grow bed so that it finds its way into the fish tank slowly.

Next day test the pH and repeat the exercise until the pH is adjusted.
If you do not detect any difference at all after two or three treatments up the amount of each treatment from a couple of tablespoons to 5 or 6 tablespoons.

Don't panic, take it slowly. Use the hydrated lime first.

[julie]

Many thanks for the help.

I'll do all my tests this afternoon and then start with the hydrated lime.

I'll keep you posted on the results.

Thanks again!


Julie

[Outbackozzie]

How did you go, and what amounts of the product did you use?

[julie]

Thanks for the email.


I did as Murray suggested and added Calcuim Hodroxide ( CaOH ) to the systems. I didn't notice any result for a few days so added more on the 4th day. The next day the ph ad swung too far the other way! But all is well as l gradually reduced the ph over a period of about a week and the system seems fine now.


I think the thing about raising or lowering ph is to do it very slowly. Even if it takes a week or so, just be patient.It will change, but it's best to take it easy.

Hope that helped!


How's your system going?


Julie

[bushboy]

Hi Julie -I've also had success with hydrated lime but find I need to
keep adding it every few days to stop it going acidic again - I wonder if this has something to do with my water "hardness" -a subject I struggle to get my brain around inspite of reading Gary's explanation in his manual

I find I need to add 1 level dessert spoon in a bucket of water - this for a 1250l system - this seems to bring the pH up 1 colour reading ( eg 6.8->7.0) - I am pretty cautious adding too much and was interested with your experience of overshoot

[Outbackozzie]

Adding a bag of crushed shells somewhere in the system will help to stabilise your Ph. It only dissolves as required, all by itself.

My system is rocking along Julie - love summer growth